This application relates to animal repellent devices; it relates particularly to a baited, shock-producing deer repellent device having an improved electrode design.
Various electrode designs have been described for shock-producing animal deterrent devices.
U.S. Pat. No. 922,377 to Ames (1909), French Patent 440,270 to Calvert (1912), and Swiss Patent 82,560 to Baumann (1919) show extermination devices for small animals with the electrodes being arranged essentially in the same plane.
U.S. Pat. No. 4,630,571 to Palmer (1986) shows an animal training device with the outer conductive case of the device being one electrode and the stake to the earth being the other.
U.S. Pat. No. 5,894,818 to Betzen (1999) describes a baited, shock-producing deer repellent device in which the electrodes are short projections above the top surface of the device.
An electrode design for use in a baited, shock-producing deer repellent device must surround the bait and protect the bait from being touched by the deer without first contacting the electrodes. If a deer touches the bait before contacting the electrodes, it will realize the bait is artificial, and the deer will then ignore the device, but it will not avoid the area to be protected where the devices are deployed.
None of these prior art devices provides an electrode design that surrounds the bait and protects it from an approach from the top and sides.
U.S. Pat. No. 6,014,951 to Betzen (2000) describes a baited, shock-producing deer repellent device with two circular, crisscrossing electrodes. With this design the distance between the electrodes varies widely. The very small distance between the electrodes at the crossing point causes the device to be easily discharged by a drop of water or by contact between the electrodes with even the slightest distortion. The very short circuit path at this top point may result in a greatly diminished effect on the deer, or the device might be completely discharged by the deer's saliva with no effect at all on the deer. On the other hand, the relatively very large distance between the electrodes at the sides of this device results in a decreased chance that the deer will contact two electrodes simultaneously. Using this design, the optimal distance between the electrodes cannot be maintained, resulting in an increased possibility that the deer will not effectively contact the electrodes and receive a shock. Also, these crisscrossing electrodes block easy access to the bait in the center of the electrodes, making it difficult to service the bait, and the horizontal aspect at the top of these electrodes tends to collect snow and ice and discharge the device.
Woodstream Corp., Lititz, Pa., manufactures a baited, shock-producing deer repellent device called the Havahart Electronic Repellent for Deer, which has two sets of semi-circular, crisscrossing electrodes. This design has all of the disadvantages of the device described by Betzen (2000), but it has an even greater chance of contact between the electrodes with distortion of the wires or by droplets of water because there are four crossing points. Also, this electrode design has an increased chance for ice and snow accumulation.
U.S. Pat. No. 6,550,428 to Betzen (2003) describes a baited, shock-producing deer repellent device with a series of parallel semicircular, electrodes arranged and sized to form an approximate hemisphere to surround the bait. While this design eliminates the crossing points, the horizontal aspect of these multiple electrodes block access to the center making it difficult to service the bait and increases the chance for accumulation of snow and ice on the device.
U.S. Pat. No. 6,779,490 to Betzen (2004) describes a baited, shock-producing deer repellent device with an insulator to keep the circular electrodes from contacting each other at the crossing point. With this insulator the distance between the electrodes at the crossing point remains very small, and moisture will discharge the device as it covers the surface of the insulator. This insulator increases the chance for snow and ice accumulation on top of the device and further blocks access to the center of the electrodes for servicing the bait. Also, this insulator further decreases chances of the deer making effective contact with the electrodes at the top of the device.
Therefore it can be seen that all of the prior art devices disclosed herein suffer from disadvantages that limit their effectiveness.
An electrode design for a baited, shock-producing deer repellent device should surround and protect the bait from an approach from the top and sides and provide a maximum chance that the deer will effectively contact the electrodes. The electrodes should have a uniform optimal distance between them to provide an ample and consistent circuit path while being close enough to facilitate effective contact with the deer. The electrodes should allow easy access to their center for servicing the bait. The electrodes should tend not to collect snow and ice. Droplets of water or a coating of water should not easily cause electrical conduction between the electrodes and discharge the device.
None of the prior art provides such an electrode design.